1. The problem asks for the measure of angle 1 in a triangle where the other two angles are 52° and 48°. 2. Recall the Triangle Angle Sum Theorem: The sum of the interior angles of a triangle is always 180°. 3. Using the theorem, we write the equation: $$m\angle 1 + 52 + 48 = 180$$ 4. Combine the known angles: $$m\angle 1 + 100 = 180$$ 5. Subtract 100 from both sides to isolate $m\angle 1$: $$m\angle 1 = 180 - 100$$ 6. Calculate the result: $$m\angle 1 = 80$$ 7. Therefore, the measure of angle 1 is 80°.